NASA’s mission will provide unprecedented insight into Earth’s surface water nose

A NASA-led international satellite mission set off early Thursday from Southern California as part of a major Earth science project to conduct a comprehensive survey of the world’s oceans, lakes and rivers for the first time.

Called Swot, short for “surface water and ocean topography,” the advanced radar satellite is designed to give scientists an unprecedented view of the life-giving fluid that covers 70 percent of the planet, shedding new light on the mechanics and the consequences of climate change.

A Falcon 9 rocket, owned and operated by billionaire Elon Musk’s commercial launch company SpaceXwas due to lift off before dawn Thursday from Vandenberg Space Force Base, about 170 miles (275 km) northwest of Los Angeles, to bring Swot into orbit.

If all goes according to plan, the SUV-sized satellite will produce research data within a few months.

Nearly 20 years in development, Swot incorporates advanced microwave radar technology that scientists say will collect surface height measurements of oceans, lakes, reservoirs and rivers in high-definition detail over 90% of the world.

“It’s really the first mission to look at almost all the water on the planet’s surface,” said Ben Hamlington, a scientist at NASA’s Jet Propulsion Laboratory (JPL) who also leads the sea-level change team. from NASA.

One of the main goals of the mission is to explore how the oceans absorb atmospheric heat and carbon dioxide in a natural process that moderates global temperatures and climate change.

Surveying the seas from orbit, Swot is designed to precisely measure the fine differences in surface elevations around smaller currents and eddies, where much of the heat and carbon reduction from the oceans is thought to occur. And Swot can do it with 10 times greater resolution than existing technologies, according to the JPL.

It is estimated that the oceans have absorbed more than 90% of the excess heat trapped in the Earth’s atmosphere by human-caused greenhouse gas emissions.

Studying the mechanism by which this happens will help climate scientists answer a key question: “What is the tipping point at which the oceans begin to release, rather than absorb, large amounts of heat to the atmosphere and accelerate global warming, rather than limit it?” said Nadya Vinogradova Shiffer, a Swot program scientist at NASA in Washington.

Swot’s ability to discern smaller surface features is also used to study the impact of rising ocean levels on coastlines.

More accurate data along intertidal zones would help predict how far stormwater flooding can penetrate inland, as well as the extent of saltwater intrusion into estuaries, wetlands and underground aquifers.

Taking an inventory of Earth’s water resources repeatedly during Swot’s three-year mission will allow researchers to better track fluctuations in the planet’s rivers and lakes during seasonal changes and major weather events.

Tamlin Pavelsky, NASA Swot Freshwater Science Manager, said that collecting this data is akin to “taking the pulse of the world’s water system, so we can see when it’s progressing and we’ll see when it’s slow.” .

Swot’s radar instrument operates in the so-called Ka-band frequency of the microwave spectrum, allowing scans to penetrate cloud cover and darkness over large areas of Earth. This allows scientists to accurately map their observations in two dimensions, regardless of weather or time of day and cover large geographic areas much more quickly than was previously possible.

In comparison, previous studies of water bodies relied on data taken at specific points, such as river or ocean gauges, or from satellites that can only track measurements along a one-dimensional line , requiring scientists to fill in data gaps by extrapolation.

“Instead of giving us an elevation line, it gives us an elevation map, and that’s just a total game changer,” Pavelsky said.